Apical Microleakage in Root Canals Containing Broken Rotary Instruments

Introduction: Broken instruments in root canals complicate routine endodontic treatment. This study aimed to compare apical microleakage in root canals containing broken rotary instruments filled with mineral trioxide aggregate (MTA), calcium-enriched mixture (CEM) cement, laterally compacted gutta-percha and injected gutta-percha. Methods and Materials: In this in vitro, experimental study, 80 extracted human premolars were decoronated and then the roots were randomly divided into four groups (n=20). Root canals were instrumented with Mtwo rotary files. The files were scratched 3 mm from the tip by a high speed handpiece and they were intentionally broken in the apical third of the canals. The middle and coronal thirds of the canals were then filled with MTA, CEM cement, gutta-percha with lateral compaction technique and injected gutta-percha. Apical microleakage was measured using dye penetration method. Data were analyzed using ANOVA and Tukey’s test. Results: Root canals filled with CEM cement showed the lowest and those filled with injected gutta-percha showed the highest microleakage according to dye penetration depth. No significant difference was noted between the microleakage of CEM cement and MTA or between lateral compaction of gutta-percha and injected gutta-percha (P>0.05). However, CEM cement and MTA groups had significantly lower microleakage than laterally compacted and injected gutta-percha groups (P<0.05). Conclusion: Due to their superior sealing ability, MTA and CEM cement are suitable for filling of root canals containing a broken instrument compared to laterally compacted and injected gutta-percha.Keywords: Broken Instrument; Calcium-Enriched Mixture; Gutta-Percha; Leakage; Mineral Trioxide Aggregate; Root Canal Filling Material

Effect of Topical Application of Dentol Drop on the Success of Inferior Alveolar Nerve Block for Teeth with Irreversible Pulpitis: A Double-blind Randomized Clinical Trial

Introduction: The failure rate of inferior alveolar nerve (IAN) block is high for mandibular molars with irreversible pulpitis. This double-blind, randomized, clinical trial aimed to assess the effect of topical application of Dentol drop on the rate of successful anaesthesia of mandibular molars with irreversible pulpitis due to deep carious lesions. Methods and Materials: Seventy-two patients with mandibular first and second molars with irreversible pulpitis and deep cavitated carious lesions participated in this study. The patients were randomly assigned to the test and control groups (n=36). In the test group, a cotton pellet, dipped in Dentol drop, was placed in the cavity for 10 min. A placebo was used _in the same manner_ in the control group. Level of pain was measured before the intervention, 15 min after anaesthesia (when patients reported numbness at the corner of the mouth), during access cavity preparation, upon pulp exposure and after introduction of the initial file into the root canal; using a Heft-Parker “Visual Analog Scale” (VAS). Data were analysed using ANCOVA. Results: Levels of pain were recorded during access cavity preparation (P<0.001), pulp exposure (P<0.001) and file introduction into the canal (P=0.018). In the test (Dentol) group, the obtained levels of pain were significantly lower than those of the corresponding values in the control group. Conclusion: Topical application of Dentol drop increased the success rate of IAN block for root canal treatment of mandibular molars with irreversible pulpitis.Keywords: Dentol Drop; Inferior Alveolar Nerve Block; Irreversible Pulpiti

The Relationship Between Strategic Thinking and Hospital Managers’ Productivity in Teaching Hospitals of Shiraz

Background: Using different methods of strategic thinking is essential for organizations such as hospitals; without them, many organizations will not survive. The aim of the present study is to evaluate the relationship between strategic thinking and management productivity in teaching hospitals of Shiraz. Objectives: Because of the importance of strategic management in organizational productivity, the present study is conducted with the goal of assessing the relationship between strategic thinking and hospital managers’ productivity. Patients and Methods: This descriptive-correlational study was conducted in 2015. The statistical population included all managers in different levels in the teaching hospitals of Shiraz (170 persons). Among these, 119 participants were selected through Cochran’s formula and a simple random sampling method. Data were collected by a questionnaire addressing strategic thinking based on Liedtka’s model and Hersey and Blanchard’s theory. Its validity was verified by a panel of experts and its reliability was measured in previous studies. Data analysis was performed in SPSS version 20 using descriptive and analytic statistics (analysis of variance (ANOVA), Pearson’s correlation test and t-test). Results: The average and Standard Deviation of strategic thinking managers was (2.2 ± 0.04), and productivity of management (2.32 ± 0.37) was estimated on the average level. There was a direct meaningful relationship between strategically thinking managers and productivity (r = 0.387, P < 0.001). The results also showed that there is a meaningful correlation between strategic thinking and sustainability, organizational support and understanding of the job. Conclusions: Due to the correlation between strategic thinking and productivity, we recommend educating and training managers in the use of strategic thinking, and that they understand its importance to productivity. Managers should understand that increasing efficiency in a competitive environment today is a necessity for survival

The Effect of Gates-Glidden Drills on the Quality of Root Canal Treatment by Pre-Clinical Dental Students

AIM: This study was conducted to investigate the effect of applying Gates-Glidden (GG) drill by pre-clinical dental students on root canal treatment quality. METHOD: A total of 56 first molars consisting of 168 canals were selected in this study. For this purpose, 56 students who had been formerly trained by two methods of root canal preparation were randomly divided into two groups (n = 28). Group 1: the step-down method by GG and Group 2: step-back technique without GG. The prepared teeth were filled with gutta-percha/ZOE sealer using lateral condensation. Periapical radiographs were taken before and the following treatment to survey occurrence of preparation errors and CBCT images to determine residual dentine at furcation region. RESULTS: The findings showed that among 10 error types in specimens prepared by students, the occurrence of underfilling, overfilling, inappropriate, ledge formation, and single cone was more common without GG. There were no significant differences in residual dentine amount at furcation region between preparation with and without using GG (P &gt; 0.05). CONCLUSION: Using GG for root canal preparation by dental students resulted in low errors and not an increased dentine removal risk

Molecular and Microscopic-Based Characterization of Plasmodium

Despite malaria control programs in recent years, malaria transmission has not been eliminated in Iran. Molecular techniques including PCR, which has proved more sensitive and specific than microscopic examination methods, help to detect infection in low levels of parasitemia and mixed infections. Main our objectives were setting up nested PCR for detection of malaria and evaluating PCR based on plasmodia DNA from blood smears in Fars province, the comparison of this method with traditional microscopy and also evaluate the data in comparison with its neighboring province, Hormozgan. A total of 149 malaria positive samples including 116, 19, and 14 samples from Shiraz, Jask, and Lengeh ports were utilized in this study, respectively. Blood slides were prepared for microscopic observation. DNA from thin smears was extracted and nested PCR was analyzed using rPLU5 and rPLU6 for genus specification, rFAL1, rFAL2, and rVIV1, rVIV2 for P. falciparum and P. vivax detection, respectively. The results showed that 126 (84.6%), 16 (10.7%), and 7 (4.7%) out of 149 cases were positive for P. vivax, P. falciparum, and mixed infections, respectively, by microscopy. The PCR indicated that 95 (63.7%), 15 (10.1%), and 22 (14.8%) cases were infected with P. vivax, P. falciparum, and mixed mentioned species, respectively, and 17 (11.4%) cases were uninfected. Our results confirmed the considerable sensitivity of nested PCR for detection of the mixed infections. Simultaneous application of PCR even based on microscopy slides can facilitate access to the highest level of confidence in malaria researches

Cystoisosporiasis-related human acalculous cholecystitis: the need for increased awareness

Cholecystitis is one of the common surgical indications affecting human beings in many countries. A variety of infectious agents can be associated with acute or chronic acalculous cholecystitis, especially in HIV/AIDS patients. In this investigation, the authors aim to describe two cases of histologically and molecularly documented cystoisosporiasis (syn. isosporiasis) as the cause of chronic acalculous cholecystitis in two immunodeficient patients. During microscopic examinations of more than 2500 diarrheic patients’ samples, 11 cases of cystoisosporiasis-related recurrent persistent/chronic diarrhea were detected. A review of the medical records of Cystoisospora belli (syn. Isospora belli)-positive patients showed that two of them, i.e. a patient with prolonged corticosteroid therapy and an AIDS patient, several months prior to fecal examinations had undergone cholecystectomy due to acalculous cholecystitis. The study was continued by a review of the histopathological investigation of the recuts prepared from the excised gallbladder tissue sections and stained with hematoxylin and eosin in order to detect a possible specific clinical correlation with cystoisosporiasis. Light microscopic examination revealed the presence of various developmental stages of a coccidial parasite, namely Cystoisospora belli , in both patients’ gallbladder tissue sections. To the best of our knowledge, C. bellii -associated cholecystitis has not been previously reported in a patient with prolonged corticosteroid therapy

734-738 Tatera indica in Estahban, Southern Iran: Microscopy, culture, isoenzyme and PCR

ABSTRACT Objectives: This study identifies the infected rodent hosts to Leishmania major in Estahban town, southern Iran during [2004][2005]. Methodology: The rodents were caught alive from April 2004 to April 2005 in Estahban town, south of Iran and examined for any skin lesion. An impression was provided from the tissues of feet, tail, ears and any patent lesion, stained with Giemsa and studied microscopically for the presence of amastigotes. All samplings were cultured at 25ºC in rabbit blood agar and considered negative if no promastigotes were visible during a two months period. The parasites from any positive culture were cryopreserved in liquid nitrogen pending their identification in PCR and isoenzyme electrophoresis. The femoral bones were histologically and ultrastrucrurally studied. Results: Among 13 captured rodents, 8 were Tatera indica (5 male and 3 female Indian gerbils) and 5 were Rattus rattus (3 males and 2 females). Just one female T. indica was smear-positive for amastigotes in Mohmmad Abad village. This rodent was also found culture positive for leishmanial infection which was confirmed by PCR and enzyme electrophoresis. At histological and ultrastructural levels, many clusters of amastigotes were noticed in the foamy macrophages of the femoral bone bone marrow. Conclusion: T. indica was found for the first time in the area and can be one of the rodents to be a potential reservoir host of L. major. It was also shown that femoral bone marrow was the tissue of choice to confirm the presence of macrophages containing the amastigote form of the parasite

Study of ZnO nano particles photocatalytic process efficiency in decolorization of methylene blue and COD removal from synthetic wastewater

Background : Effluents containing synthetic dyes are hazardous to ecological systems and public health. Methylene blue is an important chemical aromatic dye which commonly used in textile industries. Due to being aromatic, it is often toxic, carcinogenic and mutagenic. The goal of this study was to investigate the efficiency of ZnO nano particles photocatalytic process for decolorization of methylene blue by UV irradiation from synthetic textile wastewater. Materials and Methods: In this study methylene blue photocatalytic decomposition using Ultraviolet (UV) irradiation and zinc oxide nano particles having less than 50 nm in diameter was surveyed. A batch-through Plexiglass reactor having two compartment used to conduct the experiments. Wastewater was flowed to the compartment which contains of nano ZnO stabilized glasses. UV lamps were installed at another compartment. The variables of the study included: exposure time, color concentration, light intensity, and lamp distance to the catalyst surface. Results: ZnO nano particles characteristics were determined by Scanning Electron Microscope (SEM) and X-ray diffraction (XRD) analysis. Images showed that stabilizes nano particles on glass, their porosity remains in the optimal level. Optimium values for exposure time 120 minutes, color concentration 25 mg/l, light intensity 3950 μW/cm2, and distance to the catalyst surface 1 cm were achieved. At the optimal condition, methylene blue decolorization and COD removal was achieved 92.2% and 75% respectively Conclusion: Regarding the conducted experiments, the results of this studyshowed that ZnO/UV photocatalytic process has a significant efficiency in dye decolorization and COD removal. This method could be applied in the full scales

Relationship between Two Panoramic Radiography Indices and Bone Mineral Density of Postmenopausal Women with Osteopenia and Osteoporosis

Statement of the Problem: Reduced bone mineral density (BMD) generally affects postmenopausal women and it is classified into moderate (osteopenia) and significant osteoporosis. Based on digital panoramic radiographs (DPRs), several quantitative and qualitative assessment methods have been proposed for the diagnosis and evaluation of bone changes and as a predictor of BMD. Purpose: The aim of this study was to compare mandibular cortical width (MCW) and mandibular cortical index (MCI) derived from DPRs in evaluating the BMD in osteopenic and osteoporotic post-menopausal women. Materials and Method: In this cross-sectional study, the BMD assessment was performed using dual-energy X-ray absorptiometry (DEXA). Then, patients were divided into two groups: osteopenia and osteoporosis based on WHO criteria. Two types of T-scores including TT (trabecular) for lumbar spine, TC (cortical) for femoral neck and finally, MCW and MCI were measured based on DPRs. Results: Fifty females with the average age of 57.64±6.03 years were entered into the study. MCW significantly correlated with BMD (p< 0.05). Pearson correlation coefficient test revealed that there was almost significant relationship between MCI and BMD (p= 0.079). The area under the curve (AUC) in ROC suggested that there was a close overlap between MCW (0.773) and TC (0.783), but TT had the greatest AUC (0.996). Conclusion: The results showed that MCW is an appropriate index of osteoporosis in post-menopausal women. Although the prediction of osteoporosis is poorer at the femoral neck than lumbar spine, MCW can serve as a screening tool for osteoporosis in this area